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	Oct. 01, 2021	Jul. 31, 2024 USD ($)	Oct. 31, 2021 USD ($)	Feb. 28, 2019 USD ($)	Jan. 31, 2013 program	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2019 target	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Collaboration research and licensing agreements
Receivable						$ 22,073,000			$ 22,073,000		$ 11,290,000
Unrealized gain (loss) on equity securities						(10,015,000)	$ 288,000		(10,529,000)	$ (2,610,000)
Impairment on equity securities						(220,000)	0		20,430,000	0
Deferred revenue						0	7,900,000		0	7,900,000
Collaborations, milestones, and royalties						16,960,000	45,523,000		29,765,000	64,485,000
Royalties
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						0	13,300,000		100,000	27,000,000.0
Milestone
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						0	10,000,000.0		500,000	15,000,000.0
Alexion
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						6,900,000	11,200,000		16,300,000	21,600,000
MorphoSys
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						1,600,000	2,000,000.0		4,400,000	3,900,000
Mabgeek
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						1,500,000	0		1,500,000	0
Vir
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						0	100,000		100,000	1,500,000
Zenas
Collaboration research and licensing agreements
Impairment on equity securities							0		20,400,000	0
Collaborations, milestones, and royalties						0	10,000,000.0		0	10,000,000.0
Zenas \| Preferred Stock
Collaboration research and licensing agreements
Equity shares estimated fair value						43,780,000			43,780,000		64,210,000
Third Party Licensee
Collaboration research and licensing agreements
Collaborations, milestones, and royalties						7,000,000.0	0		7,000,000.0	0
Option and License agreement \| Alexion
Collaboration research and licensing agreements
Number of different target programs \| program					1
Receivable						0			0
Deferred revenue						0			0
Option and License agreement \| Alexion \| Royalties
Collaboration research and licensing agreements
Revenue recognized						6,900,000	11,200,000		16,300,000	21,600,000
Technology License Agreement \| Mabgeek
Collaboration research and licensing agreements
Deferred revenue						0			0
Collaborations, milestones, and royalties						1,500,000			1,500,000
Technology License Agreement \| Vega
Collaboration research and licensing agreements
Revenue recognized			$ 500,000
Collaborations, milestones, and royalties						0	0		500,000	0
Technology License Agreement \| Gale
Collaboration research and licensing agreements
Transaction price						7,500,000			7,500,000
Service agreement charges						4,600,000			8,000,000.0
Technology License Agreement \| Gale \| Subsequent Event
Collaboration research and licensing agreements
Payments for repurchase of preferred stock and preference stock		$ 3,000,000.0
Collaboration and License Agreement \| Genentech
Collaboration research and licensing agreements
Revenue recognized						0	0		0	0
Initial cost-sharing percentage				45.00%
Royalty milestones				$ 600,000,000
Collaboration and License Agreement \| Genentech \| Development-based
Collaboration research and licensing agreements
Royalty milestones				115,000,000
Collaboration and License Agreement \| Genentech \| Regulatory-based
Collaboration research and licensing agreements
Royalty milestones				185,000,000
Collaboration and License Agreement \| Genentech \| Sales-based
Collaboration research and licensing agreements
Royalty milestones				$ 300,000,000
Collaboration and License Agreement \| Genentech \| XmAb24306
Collaboration research and licensing agreements
Collaborative arrangement receivable (payable) related to cost sharing development activities						(7,600,000)			(7,600,000)
Collaboration and License Agreement \| Genentech \| Research service
Collaboration research and licensing agreements
Deferred revenue						0			0
Collaboration and License Agreement \| Janssen
Collaboration research and licensing agreements
Revenue recognized						0	0		0	0
Deferred revenue						0			0
Collaboration and License Agreement \| MorphoSys
Collaboration research and licensing agreements
Deferred revenue						0			0
Collaboration and License Agreement \| MorphoSys \| Royalties
Collaboration research and licensing agreements
Revenue recognized						1,600,000	2,000,000.0		4,400,000	3,900,000
Receivable						2,100,000			2,100,000
License \| Zenas
Collaboration research and licensing agreements
Revenue recognized						0	10,000,000.0		0	10,000,000.0
Deferred revenue						0			0
License \| Zenas \| Milestone \| Preferred Stock
Collaboration research and licensing agreements
Equity shares estimated fair value											$ 10,000,000.0
Second Collaboration And License Agreement \| Janssen
Collaboration research and licensing agreements
Revenue recognized						0	22,200,000		0	27,500,000
Receivable						5,200,000			5,200,000
Deferred revenue						0			0
Research license term	2 years
Second Collaboration And License Agreement \| Janssen \| Maximum
Collaboration research and licensing agreements
Percentage of responsibility for development costs	20.00%
Second Collaboration And License Agreement \| Janssen \| Minimum
Collaboration research and licensing agreements
Share development percentage	80.00%
Patent License Agreement \| Vir
Collaboration research and licensing agreements
Number of different target programs \| target								2
Receivable						0			0
Deferred revenue						0			0
Patent License Agreement \| Vir \| Royalties
Collaboration research and licensing agreements
Revenue recognized							$ 100,000		100,000	$ 1,500,000
Patent License Agreement \| Third Party Licensee
Collaboration research and licensing agreements
Receivable						7,000,000.0			7,000,000.0
Deferred revenue						0			0
Collaborations, milestones, and royalties						$ 7,000,000.0			$ 7,000,000.0